Mash efficiency

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jdooley

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Can anyone advise me about how mash efficiency is calculated. My issue is this: is it based on the final volume of beer that is bottled, or is it based on the amount that ends up in the fermenter after the mash and boil. I usually lose around 3 litres to trub before bottling. Also, the calculations regarding the amount of bitterness in the beer are also dependent on the volume. I really want to know so that I have some idea of what my efficiency is for the way I do my mash and sparge. I am hitting consistent figures, so I am happy with this, but it would be nice to know if my system is working well, and so I have more confidence in the recipes that I put together.
Thanks
 

YeastHerder

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My 2c are that because the point of knowing the number is to guide future grain bill and hopping schedules for your equipment setup, it doesn't really matter how you calculate it so long as you are consistent in how you choose to do so. So, depending on your setup, it might be easier for you to base it on different numbers than how someone else chooses to do it. That said, here is my current method:

1) Mash as usual, sparge, combine all volumes in the boil kettle
2) Measure your pre-boil SG (cooled to RT)
3) Measure pre-boil volume (a long wooden spoon with scale markings on it for your pot makes this a breeze)

I then enter the numbers into fields in BeerSmith and am typically in the 88-90% range.

I also used to do it this way:

1) Mash, sparge, combine volumes
2) Do the boil (add hops, etc)
3) Cool, transfer to carboy, top off to final volume
4) Measure OG

You can now compare the OG you actually have, to the predicted OG and the ratio is your efficiency. The reason I switched to the pre-boil measurement method is that if things are a little off, I can adjust on the fly by adding a little more or less DME in order to nail my target OG.
 

GSul

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How's it going?
I would say that it is most prevalent in your liquid that enters your primary fermenter. Even more so, your boil kettle. This is because it is the closest step right after you mash. I.e. mash efficiency. As far as I understand it, it refers to how well you extract sugars through wort from your grains. This relies on an array of variables.
As your fermentation process commences and throughout it, the yest will thrive off all the sugar they are fed. When you go to rack out of primary, there shall be no remaining sugar! It is that simple. The efficiency of your mash only references to and makes sense for the sugar fed before fermentation. That is, if you do ferment your beer. The trub is merely hope resins, proteins, husk material, dormant yeast. All of this isn't effected by efficiency of your mash, which is why it sinks to the bottom of your fermenter.
Also, I would calculate IBU at the same stage (primary fermentation). Aroma or dry hops to not add much bitterness, so can be disregarded as trub material, or even dry hops.
 

Paulgs3

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I rely on beersmith too much. But I could be wrong but you are mistaking two different things. Mash efficiency is a calculated percentage of how efficient you are at mashing (and sparging), once its in the kettle you are done with mash efficiency.

Brewhouse efficiency is the calculated efficiency from kettle to bottle.

https://www.homebrewtalk.com/f39/mash-efficiency-vs-brewhouse-efficiency-222305/
 
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jdooley

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I rely on beersmith too much. But I could be wrong but you are mistaking two different things. Mash efficiency is a calculated percentage of how efficient you are at mashing (and sparging), once its in the kettle you are done with mash efficiency.

Brewhouse efficiency is the calculated efficiency from kettle to bottle.

https://www.homebrewtalk.com/f39/mash-efficiency-vs-brewhouse-efficiency-222305/
So you are saying you need to take a gravity reading before the boil for Mash efficiency?
 

Demus

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Grains are rated based on a theoretical 100% efficiency value. Your efficiency is a percentage of that value. So MASH efficiency is just that, the resultant percentage of sugars in your mash. Pre or post boil really doesn't matter; your gravity goes up as water boils off bit this wont change your efficiency because you'll still have the same amount of sugars. For example, I think most 2 row has about a 1.036 per pound per gallon potential. So a one gallon mash at 75% efficiency would produce one gallon of 1.027 wort, or 27 "gravity points" if you want to think of it that way. If you boiled off a half gallon you'd now have a 1.054 gravity, but only a half gallon of it; still 27 gravity points, still 75% of the potential of that malt...
 

BlindFaith

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I always measure my pre-boil SG and make the calculations to see what my OG will be at for whatever volume batch I am making. That is not your complete mash efficiency though to my understanding. I have always been under the impression that your mash efficiency is the percentage of "extraction" at final wort volume BEFORE transferring to your fermentor. Your brewhouse efficiency is the percentage of extraction AFTER transferring into your fermentor taking into account any losses to hops, trub, dead space, etc....
 
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jdooley

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Demus

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jdooley said:
So it is Mash Efficiency less loss from trub?
No, mash efficiency is how much sugar you extracted from your grains. Brew house efficiency adds in ALL losses due to equipment dead space, hoses and any other wort that didn't end up in a bottle or keg...
 
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